If the camera's battery is left out of the camera for longer than one week, the camera will reset its internal memory. Try to prevent this by storing the battery inside the camera when the battery is not charging.
If the camera resets its memory, follow this process to re-configure the necessary internal camera settings:
1. On first power you will be asked to set the date and time. Do this accurately (down to the minute).
2. Place camera in "Program" mode by setting the mode dial to [P].
3. There are two menus: the system settings you get by pressing [MENU] and the photo settings you get by pressing [FUNC].
System Settings [SHOOT SETTINGS] (first tab with the camera icon):
Face ID Settings:
Camera Settings (second tab with tools icon):